Conventionally, it has been well known to form the outer wall of a building or the like with an opening section (through hole) extending therethrough in the thickness direction thereof, and insert a duct (conduit tube) in the opening section to provide communication between the inside and outside of the building via the duct and achieve ventilation of the building or the like.
However, between the inner peripheral surface of the opening section and the outer peripheral surface of the duct, a gap is likely to be formed, and water may intrude into the building from the outside thereof via the gap.
To prevent such water intrusion, a method has been proposed in which, e.g., an adhesive tape having a specified elongation or deforming stress is stuck to the duct in such a manner as to be wound therearound and also stuck to the outer wall around the opening section to seal the gap between the opening section and the duct (see, e.g., Patent Document 1 shown below).